Seeing the Distant Universe inIntegral

Field Spectrosc

opyat high

redshift

3D3DAndrew Bunker, AAO & Oxford

After era probed by WMAP the Universe enters the so-called “dark ages” prior to formation of first stars

Hydrogen is then re-ionized by the newly-formed stars

When did this happen?

What did it?

DARK AGES

Redshift z

5

10

1100

2

0

B (0.45m) U (0.3m)

VV (0.6m) II (0.8m)

JJ (1.2m) HH (1.6m)

Near Infrared

Camera NICMOS

HUBBLE SPACE HUBBLE SPACE

TELESCOPETELESCOPE

z~1 HDF spiral

U (0.3m)B (0.45m)

II (0.8m) VV (0.6m)

JJ (1.2m) HH (1.6m)

"3D" SpectroscopyPreviously used a "long slit" in spectroscopy -

cut down background light, become more

sensitiveRelatively new technique

- integral field spectroscopy - arrange elements to survey a 2D area (rather than a 1D

line)The spectra gives a 3rd

dimension (wavelength, or velocity)

Integral Field Spectroscopy

Cambridge IR Panoramic Survey Spectrograph

What is CIRPASS?

Near-infrared integral field unit (spectra over a 2D area)

Built by the IoA with support of Sackler foundation & PPARC

Wavelengths 0.9-1.8m (z, J, H): doubles range of Gemini IFU science

490 spatial samples & variable image scales 0.05"-0.33" up to 5"x12" field

Large wavelength coverage (=2200Å) at R~4000: great sensitivity between OH sky lines

Limiting line flux on an 8m ~2x10-18 ergs/sec/cm^2 (53 hours)

Successfully demonstrated in August 2002 on Gemini-South telescope, community access 2003A

500 fibres IFU

Instrument cryostat

On dome floor

Sky "glow" in the near-IR

IFU Science

●Exquisitely sensitive to line emission redshifted between OH

●Star formation at z>1 (H, [OIII]5007Å, H, [OII]3727Å)

●Robust star formation rate measures down to

1M⊙/yr●Rotation curves, kinematics

●Masses, extinction, metallicity

●Nature of damped Lyman- systems at high-z

●Lensed galaxies/dark matter sub-clumping

●Ages of young star clusters

Gemini Integral Field Spectroscopy

– Program with Gemini Observatory to demonstrate the power of IFUs (5nights GMOS+8 nights CIRPASS)

Large interntational team (CIRPASS observations involve ~50 scientists) lead by Cambridge/Gemini/Durham

First demonstration of near-IR IFU science

Institute of Astronomy, Cambridge: Andy Bunker(AAO/Oxf), Joanna Smith (PhD student), Rachel Johnson (Oxf), Gerry Gilmore & Ian Parry, Rob Sharp, Andrew Dean etc CIRPASS team

Gemini: Matt Mountain, Kathy Roth, Marianne Takamiya, Inger Jørgensen, Jean-Rene Roy, Phil Puxley, Bryan Miller, etc. (Director's discretionary time)

Durham: Richard Bower, Roger Davies (Oxf), Simon Morris, Mark Swinbank etc. & GMOS team

Andrew Bunker, Gerry Gilmore

(IoA, Cambridge) & Roger Davies (Durham/Oxford

)

GMOS-IFU

GEMINI-NORTH

optical: Gemini Multi-Object Spectrograph

Hawaii June 02

GEMINI-SOUTH

Chile Aug '02,Mar/Jun 03

Q2237+03 - Einstein cross

Search for dark matter

substructure - Ben Metcalf,

Lexi Moustakas,

Bunker

z=1.7 QSO, z=0.04 lens

Substructure at 104M⊙<M<108M⊙ is 4%-7% of surface mass density - high compared to some CDM predictions

(but poss. variability/microlensing)

Q2237+03 - Einstein cross

Ben Metcalf, Lexi

Moustakas, Andy Bunker &

Ian Parry (2004,

accepted by ApJ, astro-ph/0309738)

Extended blue light over >5", aligned with radio

3C radio galaxy z=1.2 deep HST im.

studied by Spinrad & Dickinson

evidence of a cluster

size well-suited to GMOS/CIRPASS

study emission lines [OII] & [OIII]/H (kinematics)

A z=1.2 radio galaxy 3C324(Joanna Smith PhD)

[OIII] map in 3D of a z=1.2

galaxy (Smith, Bunker et al.)

Semi-raw frame

Sky (xy)

(xz)

(yz)

HST B-band (rest-UV)

GMOS-IFU [OII]3727

CIRPASS [OIII]5007

HST R-band

3C324 alignment effect, with Joanna Smith (PhD student)

GMOS IFU Spectroscopy Gemini-N 3C324 z=1.21 radio galaxy -

"reduced" 2D (still has sky & cosmics, but extracted fibres)

8000Å 8300Å

[OII]3727Å @z=1.2

3C324 3-D data

cube

[OII]3727 structure has two velocity components at +/-400km/s

Wavelength/

velocity

HST B-band (rest-UV)

GMOS-IFU [OII]3727

CIRPASS [OIII]5007

HST R-band

3C324 - Smith, Bunker, et al. : alignment effect

Galaxy kinematics redshift 1!

H map of a CFRS disk galaxy

with CIRPASS (Smith, Bunker et al., submitted)

[OII]3727Å doublet, ~300km/s velocity shift

Wavelength/

velocity

z=1 arc 3D data cube

z=1 arc de-lensed

Mark Swinbank, Joanna Smith, Richard Bower,

Andrew Bunker et al

[OII]3727Å velocity map

HST/WFPC (B,R,I) F450W, F606W, F814W

sky (lensed) de-lensed

Galaxy Kinematics at High Redshift:

Why do we care?

- For disk galaxies, velocity at flat part of rotation curve correlates with the stellar mass of the galaxy (I- or K-band) - the Tully Fisher relation-How does this scaling relation evolve with time?- In "classical" model, dark halo forms first, and disk forms later: M/L decreases with time.-So circular velocity at a fixed stellar mass less in the past- BUT in hierarchical assembly, make galaxies through mergers, so stellar mass vs. circular velocity follows same relation over a wide range of redshifts- Can test this through rotation curves of z~1 galaxies- Use rest-optical lines redshifted into near-infrared- IFUs ideal - no uncertainty of slit axis vs. galaxy axis

Emission lines ⇒ Star formation rates,

metallicity, dust extinction, kinematics

Damped Ly- QSO Absorption Systems

Bunker, Warren et al.

Star formation in damped Ly- systems(Joanna Smith PhD)

CIRPASS refereed Publications "Spectroscopic Gravitational Lensing and Limits on the Dark Matter Substructure in Q2237+0305" R.B. Metcalf, L.A. Moustakas, A.J. Bunker & I.R. Parry ApJ (astro-ph/0309738)

"Extragalactic integral field spectroscopy on Gemini" A. Bunker, J. Smith, I. Parry, R. Sharp, A. Dean, G. Gilmore, R. Bower, A.M. Swinbank, R. Davies, R.B. Metcalf & R. de Grijs (astro-ph/0401002)

"CIRPASS near-IR integral field spectroscopy of massive star clusters in the starburst galaxy NGC1140" R. de Grijs, L.J. Smith, A. Bunker, R. Sharp, J. Gallagher, P. Anders, A. Lancon, R. O'Connell & I. Parry; MNRAS (astro-ph/0404422)

"The Tully-Fisher Relation at z~1 from CIRPASS near-IR IFU H-alpha spectroscopy" J. Smith, A. Bunker, N. Vogt et al. MNRAS 2004

Seeing fluorescence from neutral hydrogen

5"

200Å

20"

zem=4.487

Spatially Extended Ly- Emission

z=4.5 QSO illuminating its protogalaxy

Extended Ly- , narrow (FWHM~1000km/s)

Central QSO (solid line)

broad Ly-Extended narrow Ly- (dashed

line),no continuum

Recombination line probably powered by reprocessed QSO UV flux rather than by local star formation.

The HI cloud of the host galaxy is

~>35kpc/h70 (=0.3)

SPH simulations, distribution of neutral gas at z~3 (from Katz et al. and Rauch, Haehnelt & Steinmetz).

Left box is 22Mpc comoving, 15arcmin; right zoomed x10

Wavelength/Å

The catch: very faint low surface brightness

The deepest spectrum in the Universe?

Rauch, Haehnelt, Bunker, Becker et al. (2007)

Win with IFUs rather than long-slit: MUSE?

DAZLE - Dark Ages 'z' Lyman-alpha Explorer (IoA - Richard McMahon, Ian Parry; AAO - Joss

Bland-Hawthorne

"Lyman break

technique" - sharp

drop in flux at

below Ly-.

Steidel et al. have

>1000 z~3 objects,

"drop" in U-band.

Pushing to higher

redshift- Finding

Lyman break galaxies

at z~6 : using i-drops.

The Star Formation

History of the Univese

Bunker, Stanway, z=5.8

Ellis, McMahon

& McCarthy (2003)

Keck/DEIMOS

spectral follow-up

& confirmation

I-drops in the Chandra Deep

Field South with HST/ACS

Elizabeth Stanway, Andrew

Bunker, Richard McMahon

2003 (MNRAS)

Galaxies at z~6 are small - barely resolved by HST. E-

ELT diffraction limit ~0.01” (~50-100pc). See individual HII regions?

What is JWST?● 6.55 m deployable primary

● Diffraction-limited at 2 µm

● Wavelength range 0.6-28 µm

● Passively cooled to <50 K

● Zodiacal-limited below 10 µm

● Sun-Earth L2 orbit

● 4 instruments

– 0.6-5 µm wide field camera (NIRCam)

– 1-5 µm multiobject spectrometer (NIRSpec)

– 5-28 µm camera/spectrometer (MIRI)

– 0.8-5 µm guider camera (FGS/TF)

● 5 year lifetime, 10 year goal

● 2014 launch

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

NASA/ESA/CSA - JWST● NIRSpec

– ESA near-IR MOS to 5um, 3’x3’

● NIRCAM - 3’x3’ imager <5um

● FGS (Canada) - has tunable

1% narrow-band NIR filters

in

● MIRI - mid-infrared

Europe/US

QuickTime™ and aTIFF (LZW) decompressor

are needed to see this picture.

(closely similar to HST model…)

NIRSpec IST

Absorption lines at z>5 - a single v. bright Lyman

break z=5.5 galaxy, Dow-Hygelund et al (2005),

AB=23-24, VLT spectrum (22 hours), R~3000; S/N=3-10 at

R=1000,2700 in 1000sec NIRSpec

E-ELT

For I-drops (z~6) would only get ~1 per NIRSpec field bright enough for S/N~3-10 in continuum in 1000sec for abs line

studies

Does AO Help you?

-If Ly-alpha is compact, AO will boost point-source sensitivity-- Unclear if this will be the case - extended Ly-alpha haloes known, and expected through resonant scattering (see the far edge of the ionized bubble)

--For morphological analysis, unclear that high-tech ELT AO is better than a poorer but better-quantified PSF (e.g. from space)--If you can’t quantify where 10-20% of the light goes from a centrally-condensed core, that’s the difference between a disk and bulge morphology when fitting Sersic index--Even worse when looking for QSO host galaxies…

Conclusions-- 3D IFU spectroscopy at high redshift is (finally) realising its potential, but still small sample sizes--Important as a probe of galaxy kinematics, and spatially-resolved maps of stellar populations, metallicity-- Trace the evolution of the assembly of stellar mass--Explore the nature of gravitational lenses (dark matter)-- Explore the nature of the galaxies responsible for QSO absorption lines--In future might see fluorescence of the HI gas--Compact galaxies at high-z: need AO on ELTs to get real IFU benefit

GMOS-IFU (Swinbank et al. 2003)

Tully-Fisher at redshift 1!

Swinbank, Smith, Bower, Bunker et al.

HEALTH

WARNING!

CFRS22.1313

CIRPASS H

Lensed arc z=1

GMOS [OII]